As a method of manufacturing a bearing ring (inner race or outer race) of a bearing, cutting and grinding are carried out as described in Patent Literature 1. For example, in a method of manufacturing (processing) the outer race, processes illustrated in FIG. 4 are sequentially carried out.
First, as illustrated in FIG. 4A, an outer race blank W1 that is processed into an almost finished shape of an outer race is obtained by forging such as cold rolling. The blank W1 is quenched in a heating furnace 52 to be subjected to surface hardening as illustrated in FIG. 4B, and then width grinding illustrated in FIG. 4C and outer diameter grinding illustrated in FIG. 4D are carried out on the blank W1. Next, the blank W1 subjected to the outer diameter grinding is turned, and then as illustrated in FIG. 4E, a rolling surface 51a and seal grooves 51b are processed into desired shapes. Finally, as illustrated in FIG. 4F, the rolling surface 51a is superfinished using a grindstone 53. Thus, the blank W1 is completed as an outer race 51.
The same processes are carried out also in a case of manufacturing (processing) the inner race. That is, an inner race blank that is processed into an almost finished shape of an inner race is obtained by forging such as cold rolling. The blank is quenched in a heating furnace to be subjected to surface hardening, and then width grinding is carried out on the blank. Next, the blank subjected to the width grinding is turned, and then a rolling surface and seal grooves of the blank are processed into desired shapes. Inner diameter grinding is performed on the blank thus cut, and superfinishing is performed on the rolling surface of the blank using a grindstone. Thus, the inner race blank is completed as an inner race.